Dishwashing machine



March 30, 193 7.

G. B. GRACE ET AL DI SHWASHING MACHINE Filed April 7, 1953 F'IE I.

5 sheets sheet 1 INVENTORS [cu/'5 [ans/ 79 March 30, 1937. G, G E ET-AL 2,075,034

DISHWASHING MACHINE Filed April 7, 1933 5 Sheets-Sheet 2 'INVENTORS 1 1041/15 P. [ans/fig 4 BY Gordon 5. 5/Jce Jw A TTORNE YS.

March 30, 193 7.

G. B. GRACE ET AL 2,075,034 DISHWASHING' MACHINE Filed April 7, 1933 5 Shts-Sheet 5 INVENTORS [cu/Is P. Zens/71g araon 5. Grace Patenteci Mar. '30, 1937 UNITED STATES PATENT OFFICE DISHWASHING MACHINE Gordon B. Grace and Louis I. Lansing, San Francisco, Calif.; said Grace assignor to said Lansing Application April '1. 1933, Serial No. 664,914 11 Claims. (01.299-63) ularly to washing machines such as are employed.

for the washing of dishes, glasses and like articles of tableware.

It is a general object of the invention to devise a dish washing machine which will be a marked improvement over machines which have been developed in the past for this purpose, particularly with respect to the universal effectiveness of the washing action secured, and with respect to capacity and power consumption.

A further object of the invention is to provide a dish washing machine which will have a relatively wide latitude of application, and which, for example, can be used for the washing of tumblers or glasses, as well as for the washing of heavier tableware such as plates.

A further object of the invention is to provide mechanism, useful in machines of the above character, for the pumping and forcible spraying of water or other liquid, and which will be characterized by many features and advantages not inherent in mechanism for this purpose in the prior art. For example, the mechanism disclosed therein for' the pumping and spraying of liquid makes possible an adjustment over asubstantial range with respect to the quantity of liquid handled, while the velocity of the particles of the spray remains substantially constant. p

A further feature of our mechanism is that its rotating part or parts are not apt to be damaged .by articles, such as knives and forks, failing upon' from the following description in which the preferred embodiment of the invention has been set forth in detail in conjunction with the accompanying drawings. The appended claims are to be accorded a range of equivalents consistent with the state of the prior art.

Referring to the drawings:

Fig-1'is a plan view','-illustrating a dish washing machine incorporating the present invention, with a part of the cover broken away to expose certain parts to view.

Fig. 2 is a. cross-sectional detail takenalong the line 2-4 of Fi 1. I

Fig. 3 is a side elevational view, partly in transverse cross-section, except for the pumping and spraying mechanism, and taken particularly along the line 3-3 of Fig. 1.

Fig. 4 is a cross-sectional view taken along the line 4-4 of Fig, 3.

Fig. 5 is a side elevational detail, illustrating a portion of the manual control means for the pumping and spraying mechanism, and for the spraying of rinse water.

Fig. 6 is a cross-sectional detail taken along the line 6-6 of Fig. 1.

Fig. 7 is a cross-sectional detail taken along the line |-1 of Fig. 9, illustrating the arrange,- ment of a spray nozzle for rinse water.

Fig. 8 is a cross-sectional detail taken along the line 8-8 of Fig. 9.

Fig. 9 is a cross-sectional detail-taken along the line 9-9 of Fig. 6. Fig. 10 is a cross-sectional detail taken along the line IO-III of Fig. 6. w 7

The particular dish washing machine illustrated in the drawings consists generally of a liquid reservoir or. tank, III, carried by a suitable supporting means or stand I I. Adapted to overlie reservoir III when the machine is operating-there is a cover I2, in the form of an inverted container as will presently be explained. Arranged within the space enclosed by reservoir III and the cover I2, above the water in reservoir loythere is a. dish supporting means I3. Arranged below the dish supporting means and within reservoir I0, there is a pumping and spraying mechanism designated generally at II.

Although the reservoir III and its supporting stand ll may obviously vary widely in construction, certain of the.details as illustrated in the drawings will be pointed out, to facilitate a subsequent description of the working parts. As is apparent from Figs. 1 and 3, the reservoir. I0 is rectangular in contour, being formed of front and rear vertical walls I6 and I1, side walls I8,

and bottom wall I9. The supporting stand for 'the reservoir includes a pair of legs 2| having their upper ends secured to the forward comers of the reservoir, together with apair of spaced vertical channels 22 secured to the rear wall I'I.

part 26, made of metal or other suitable material,-

with an upper part or closure 21 made of glass or like transparent material. A depending annular ridge 28 has been shown formed on the under side of part 21, to more effectively direct water back upon top of the dishes, and back into the reservoir Hi. In order to more conveniently move the cover I2 from the operating position illustrated in Fig. 3, to an elevated and out-ofthe-way position, the cover has been shown connected with suitable means guided for vertical movements, and suitably counterbalanced. Thus mounted on the rear-side of cover l2, there is a stamping or casting 29, which in turn is secured to a pair of spaced depending angle members 3|. Extending laterally thru the angle members 3| are the shafts 32 (Fig. 1), and upon the ends of these' shafts, rollers 33 are journaled. These rollers are accommodated within the channels 22, and engage the channel flanges, thus guiding the angle members 3| and the cover |2 for vertical movements. To serve as counterbalancing means, we have shown a weight 36 which is connected to the lower shaft 32 thru a cord or bable 31. Cord 31 passes over a pulley 38, whereby when the cover l2 together with the associated angle members 3| is raised, weight 36 is lowered. The counter-balancing effect is preferably such as to enable the cover to be retained either in an elevated out-of-the-way position or in a lowered operating position as shown in Fig. 3.

It is apparent that the relationship of the cover with respect to the reservoir II) should be such that when the cover is in a lowered operating position there will be no splashing of water from the space thereby enclosed. Likewise, it is desirable to provide means surrounding the upper part of the reservoir to'catch refuse. Therefore, the top of reservoir III has been shown provided with a cover plate 4| which has an inner annular opening bounded by the annular ring 42. Surrounding ring 42, there is an annular upstanding flange 43, adapted to accommodate the lower edge of cover l2, shown in Fig. 3. The outer edge of plate 4| can be rectangular in contour, similar to the outer contour of reservoir l0, and is shown provided with an upstanding flange 44. Thus, a trough 46 is formed between flanges 43 and 44, to catch refuse (Fig. 3). As shown more clearly in Fig. 2, liquid received by trough 48 may be drained thru a depending tube 41, the lower end of which has been shown accommodated within the upper open end of an overflow pipe 48 ,within reservoir l0. Overflow pipe 48 leads to a drain pipe 48, communicating thru the bottom wall |9 of reservoir The dish supporting means |3 can be variously constructed, but, as illustrated, is in the form of a rotatable basket. This basket consists of a bottom 5| of wire screening or like material which will pass a spray of water, and which is secured to the lower edge of an annular wall 52. This basket is adapted to removably rest upon the radial spokes 53 which are secured to the upper end of a rotatable shaft 54. The outer ends of spokes 53 are connected by an annular flanged ring 58 which also serves to centrally locate the basketwith respect to the center of rotation of shaft 54. Shaft 54 is removably positioned within a socket 51, which in turn is carried by webs 58, these webs being connected to the removable ring 42. The lower end of socket I! is shown provided with an anti-frictionthrust bearing 58, to engage the lower end of shaft 54. Removably positioned between certain of the webs, we have shown quadrant-shaped, foraminous trays 6|, which may catch larger sized solid material removed from the articles being washed. It may be noted at this point that no tray of, this character should be positioned immediately above the pumping and spraying mechanism I4, as illustrated in Fig. 1.

The pumping and spraying means M can better be understood by reference to Figs. 6, 8, 9, and 10, and is constructed as follows:-The bottom wall I!) of the reservoir I0. is provided with an opening to accommodate a member 66,- which can be in the form of a' casting. As will be presently explained, this member is preferably constructed to function both as a means for directing flow of water to a rotary impeller and for shrouding the drive shaft for the impeller. Referring to Fig. 6, member 66 is shown provided with an annular flange 61, underlying a portion of the bottom wall I9, and sealed with respect to this bottom wall by suitable means such as a gasket 68. The curved upper surface 69 of this member 66 serves to direct flow of water inwardly and upwardly towards the impeller, while the upper annular portion H serves as a shroud. Mounted upon the curved flow directing surface 69 are a plurality of vanes or fins 12. As is evident from Fig. 9, these vanes are set at an. inclination with respect to radii from thecentral vertical axis of member 66, to impart swirling movement to water flowing inwardly over surface 69.

Disposed above and surrounding portion ll of member 66 there is what can be termed a bowl structure 13. The upper portion 14 of structure 13 is bowl-like in shape, that is, it is belied outwardly, while the lower portion 16 is shown substantially cylindrical, to surround the rotary impeller to be presently described. Secured to the lower edge of the portion 16 of the bowl structure, there is a relatively flat annular ring 11 having upwardly turned inner and outer peripheral edge portions 18 and 19. The annular space between ring 11 and the curved surface 68 forms what can be termed an inflow opening 8|. The bowl structure is adapted to rest upon bosses 88 which are formed upon the upper side of casting Eli.

Arranged within the cylindrical portion 16 of the bowl structure, there is a rotary impeller 82. In the detailed construction illustrated, this impeller is formed with a circumferential shroud 83, having a plurality of vanes 84 mounted upon its inner periphery. These vanes are provided with a proper lead, with respect to the direction of rotation, so that they serve to pick up'water flowing inwardlythru inflow opening 8|, and discharge the same'as a sheet of water upon the inner surface of bowl portion 14. I,

In order to mount the impeller 82 for rotation about a vertical axis, and for driving the same, we have shown an electric motor 86. Lugs 81 serve to secure the frame of this motor to the under side of casting G6. a One end of the motor shaft 88 is coupled to a shaft extension 89, the upper end of which terminates adjacent the upper end of shroud 1|- Mounted upon the upper end of shaft extension 89, by suitable means such as a cap screw 90, there is an inverted cup-shaped member 9|. The lower part of this cup-shaped member 9| surrounds a machined cylindrical surface 92 on shroud portion 1|, there being a slight clearance, however, to permit free turning. Removably disposed over the cup-shaped member 9|, there is a similarly shaped member 98. This member, however, is formed with a non-circular portion 94, to provide a disengageable driving connection with the head of cap screw 90. The lower edge portion. of cup-member 93 is'secured to the upper .and inner corners of vanes 88, by suitable means, such as welding. In order to avoid any possible contact of water with the bearings and windings of the electric motor 86, the motor shaft has been shown provided with a dished annular splash plate 98, whereby any water or liquid entering shroud portion It is thrown outwardly.

Insofar as the pumping and spraying mechanism has been described, it is evident that water flowing thru inflow opening M is acted upon by the impeller '82, to impart both rotary and vertical velocity components to the same. The sheet of water thereby delivered upon the inner surface of the bowl-like portion It, is discharged from the lip 9! in the form of a conical spray, in which the particles tend to twist or progress in the direction of rotation of the impeller. In other words when the particles of water are thrown from ,the lip 97, they have imparted to them velocity components in an upward or vertical direction, in an outward direction by virtue of removal of restraint aiIorded bythe bowllike portion I5; and also in a rotary direction If the water, at the head in which it normally exists in reservoir III, is permitted to flow directly into the inflow opening 8i, 'it will be dimcult to properly control the capacity of the mechanism between desired limits. In solving this problem we have made it possible to adjust the pumping capacity thru a substantial range, while the velocity imparted to the particles of the spray remains substantially constant. Thus to afiord a novel-form oi throttling means, we provide an open-ended cylinder or throttling member IIIII, which loosely surrounds the bowl structure I3. The lower edge 01 this cylinder is adapted to rest upon the upper surface of casting 66. To afiord means for vertically adjusting the position of cylinder IOI, we have shown a pair of rods I02 having their upper ends secured to an annular apron I03. Thisapron is in turn fixed to the upper end of cylinder IOI. Rods I02 slidably extend thru tubular standards I04, to the exterior of the reservoir I0. The lower ends of these standards I04 may be threaded to serve as means for clamping the annular flange to the bottom wall I0 01' the reservoir- In order to control the positioning of cylinder extends to the .front side-.0! the machine, .where itisprovided with ahandle or knob III. A suitably slotted lock plate II2 is also provided in conjunction-with operating leve'r I09, whereby this lever can be locked in various adjusted positions. A link III has its one end pivotally connected to operating lever I09 and its other end connected to a crank Ill, which is fixed to shaft I06. Thus when lever I is in a neutral-posh 1 tion as shown in Fig. 5, cylinder IN is permitted to contact with the upper surface of casting. However upon upward movement of lever I09 from its neutral position, cylinder IOI is elevated, to afford an annular orifice between its lower edge and the upper surface of casting 66, thru which water may flow by gravity.

With respect to the cylinder or throttling member II", it should be noted that space between this member and the bowl structure I3, which has been indicated by numeral H4 in Fig. 6, is vented to the atmosphere thru apertures H5. It will be noted that these apertures are above the normal level ofwater within reservoir l0. The advantages to be obtained by venting this space to the atmosphere will be presently explained.

When the cylinder IN is in its lowered or closed position, there is substantially no spraying of water, since water cannot enter the inflow opening 88. Therefore it is desirable that cylinder IOI remain closed during such times as the cover I2 may be elevated, and that movement of cylinder I0! to an elevated position to efiect spraying of water, be permissible only when the cover I2 is in closed or lowered position. To make possible these functions, we provide an ,interlock mechanism as followsz-Benoath the reservoir I0 (Fig. 4) there is a rod H0. The slidably mounted rear end of this rod terminates in close proximity to one of the vertical angles 35,

while the other end is pivotally connected to a crank II'I, fixed with respect to rock shaft I06. When angle members M are in their lowermost position, corresponding to closed position of the cover I2, sliding movement of rod H6 which accompanies upward movement of arms IN, is accommodated by an aperture H8 (Fig. 4). However when cover I2, together with the angles Si,

is in an elevated position, sliding movement of rod lid is constrained, so that arms III'I cannot be elevated to open the throttling member I09. Likewise in the event the throttling member IilI is in open position while the cover I2 is closed, positioning of rod H in aperture H8 locks the cover in such position.

A'novel feature of our pumping mechanism is the provision of means in conjunction with the impeller 02, whereby the water delivered from this impeller is caused to flow thru an automatically variable orifice. Thus overlying the impeller we have shown what can be termed a flap I2I. The upper portion I22 of the flap is cupshaped, similar to the formation of members 9| and 93, and a. non-circular portion I23 is also provided to form a slidable but driving fit with the portion 94 over which it fits. The lower .fiange portion I24 of the flap is annular in contour, and is arranged to overlie the vanes of imorifice I26 for the delivery of water is formed between the outer peripheral edge of flange portion I24, and the upper edge of the impeller shroud 03,. As the quantity of water being handled by the mechanism increases,- orifice I26 is automatically increased accordingly, by elevation of the den I 2I. In other words the peripheral edge of flap portion I24 rides upon the stream of water being discharged from the impeller.

Undesired fluttering of the flap is minimized by'a dash pot action, because of its telescopic reutilizing a free rotating basket for supporting the dishes to be washed, the pumping and spraying mechanism I4 previously described, is pref erably offset with respect to the axis of the baskept supporting shaft 54. The twisting characterof the spray causes the dish supporting basket to be rotated, by the reaction of the spray of water upon the basket and the articles which may be supported within the same, and the offset relationship makes possible better washing action and a properly regulated speed of rotation without the use of braking means.

Upon the conclusion of a washing cycle, it is desirable to provide a spray of clean water for rinsing. co-ordinate the means utilized for spraying rinse water, with the control for the pumping and is thereby flattened and caused to discharge as a, sheet of water thru the annular opening I33. Pipe I34, connected to port I3I, leads to an external water pipe I30, and is also connected with an auxiliary spray pipe I35 for directing a jet of water upwardly along one side of the cover I2. Interpos'ed between pipe I34 and pipe I36, there is a control valve I31 01 the poppet or plunger type, having an operating stem I38 which is biased toward closed position, and which must be forced downwardly to open the same. Mounted upon the operating lever I09 there is a cam member I39 (Fig. 5), adapted to engage and actuate plunger I38, when lever I09 is moved to its lowermost position.' With such an ah rangement, it is obviously impossible to introduce rinse water by way of nozzle I32, except when the throttling member IN is in closed position. We likewise preferably provide an interlock mechanism, whereby rinse water can only be introduced into the machine when the cover I2 is in closed .position. For this purpose there is shown a rod I4I, similar to rod H6, below the reservoir I0. The slidably mounted .rear end of this rod I4I terminates adjacent to one of the vertical angles 3|, while the other end of this rod is connected to a crank I42 mounted upon rock shaft I06. It will be noted that crank I42 is displaced degrees with respect to crank I I1. When the cover I2 is closed, the rear end of rod I4I isadapted to be accommodated in aperture I43 provided in the associated angle 3|. With such an arrangement it is likewise impossible to lift the cover I2 while rinse water is being injected, or to introduce rinse water while the cover is elevated.

t is desirable to prevent entrance of foreign material of any considerable size into the pumping mechanism, as for example small articles of table ware being washed or foreign material from the same. For this purpose a screen or strainer I 44, which can be cylindrical in shape, is shown surrounding. the throttling member IOI, and has its lower edge resting upon the bottom wall I9 of the reservoir I0. The upper edge of this screen underlies the apron I03.

Where the machine is being employed continually, it is desirable to provide for the heating of wash water within reservoir II). For this purpose we have shown a suitable heating element We have also found it desirable to' from the bowl lip 91.

in the form of a gas burner I46, beneath the bottom wall I0. Apipe connection I41, controlled by a valve I48, has also been shown for replenishing or replacing the wash water.

Before explaining the mode of operation of the machine, it should be noted that the pumping mechanism has many of its parts readily removable, thus facilitating cleaning of the machine. Thus if it is desired to clean the pump ing mechanism, throttling member IOI can first be bodily lifted from the machine. Removal of the throttling member permits removal of the strainer I44. Bowl structure I3 can likewise be lifted from its operating position, without the necessity of removing bolts or like fastening means. The flap I2I can likewise be lifted from its position upon the impeller 82, and then the impeller itself can be removed, to permit cleaning of the upper surfaces of casting '66, or for inspection.

Operation of the machine can be outlined as follows:While the cover I2 is elevated, and operating lever I09 in neutral position, the basket is loaded with articles of tableware, and positioned within the machine as shown in Fig. 3.

At this time it is presumed that reservoir I0 contains an ample quantity of wash water, with the upper level of this water somewhat below the level of apron I03. Upon closing the cover I2 the operator liftsthe lever I09. Lifting of this lever causes a lifting of the throttling member IOI, to admix water to the inflow opening 8| of the pumping mechanism. Water picked up by the impeller 82 is discharged as a conical spray This conical spray strikes the articles of tableware in the basket with considerable velocity, and any part of the spray which is not immediately deflected back into the reservoir I0, may be deflected back upon top of the tableware by the cover l2. .Because of the fact that particles of the conical spray progress about its axis, the reaction of the spray upon the basket and upon the articles therein forms a torque tending to rotate the basket and its contents. Because the axis of the spray is offset with respect to the axis of rotation of the basket, the reaction torque is the resultant of two oppositely directed components. Thus the spray particles striking that portion of the basket near its outer periphery tends to rotate the basket in one direction, while the spray particles striking that portion of the basket near its center of rotation tend to rotate the basket in the opposite direction. However since points of impact are at difierent radii from the axis of rotation of the basket, there is a net resultant torque component to cause rotation. Rotation of the basket in this fashion brings all of the articles of tableware repeatedly into the range of operation of the spray. The speed of rotation is automatically prevented from becoming too rapid, without the use of mechanical braking means, by the oppositely reacting components of the spray particles upon the basket and contents as previously explained. Too rapid rotation of the hasket is objectionablenot only because of possible displacement or injury to the tableware, but also because poor washing action would result.

The quantity of water handled by the pumping and spraying mechanism is dependent upon the height to which the operating lever I09 is set above its neutral position. Over a substantial range of this adjustment, the velocity of impact of the particles of the spray upon the tableware remains substantially constant. although the quantity of the water sprayed is varied. This characteristic of our machine makes it possible to make adjustments to secure eflicient washing of various types of tableware. For example, with plates or like articles, it is desirable to operate the pumping and spraying mechanism M at substantially full capacity. However, where the basket is loaded with tumblers, cups or fragile ware, it is desirable to operate at somewhat less than full capacity, for the reason that full ca-. pacity operation would react so strongly upon the articles as to cause them to be lifted and displaced, and might not afford opportunity for the water to immediately flowaway from interior surfaces being cleaned by impact. However, because of thecharacteristic of our machine which has previously been explained, that is that the capacity can be decreased to a. substantial degree without a corresponding decrease in the velocity of the sprayed particles, tumblers and cups may be washed eficiently, and fragile articles can be washed without clattering which might cause chippage or breakage. After completion of the washing cycle the operator moves lever Hie downwardly thru neutral position, to the lowest position indicated in Fig. 5. This causes the valve 037 controlling the rinse water to be opened, thus subjecting the articles within the basket to a spray of clean rinse water discharged from nozzles I32 and 835. At this time the basket i3 continues to rotate, by virtue of the momentum attained during the washing cycle. After the rinsing operation, lever B69 is returned to neutral position, and then cover i2 can be lifted to permit removal of the washed articles.

With respect to the pumping and spraying mechanism, it has previously been stated that when throttling member ID! is in open or partially open position, it permits an inflow of water to the inflow opening 8i by virtue of the gravity head within reservoir Ill. The fact that space i It immediately within throttling member IN is vented to the atmosphere, makes it possible for the flow of water beneath throttling member IM to occur in accordance with the laws of flow of liquid thru an orifice under a gravity head, because no suction can be applied to the annular orifice below the throttling member. During normal operation the level of water in space H4 falls to a level in the neighborhood of the lower end of bowl structure I3.

In further explanation of operation of flap Hi, the orifice I26 is filled with water throughout substantially the entire range of adjustment of the throttling member llll, except for closed or nearly closed throttle positions. An air space exists within the impeller and below flap I2 I, and

except for closed or nearly closed throttle positions, the flow of, water thru orifice I26 functions as an air exhausting pump to continuously exhaust or aspirate'air from this space. This evacuated space is in restricted communication with the atmosphere thru the clearance between member SI and cylindrical surface 92, and except for full or substantially full open throttle positions,

' also receives air thru the inflow opening together where insufficient water is discharged by the impeller to fill orifice I26.

The fiap, and the suction created below it as explained above, has a marked effect upon the capacity of the mechanism. For example, with the flap the capacity of. the pumping mechanism is increasedmany times compared with the capacity without the. flap. Increasing the rate of infiow of air, as by providing an additional vent aperture in the flap, decreases thepumping capacity for a given setting-0f the throttling member Hill.

The action of the fiap i2! also makes possible the use of an impeller which is not provided with an inner restraining wall for the water flow. If an impeller having both inner and outer restraining walls were employed, a high capacity could be secured without the use of a flap, but the desired degree of regulation by adjusting throttling member illi would not be obtained.- With our construction, high capacity is secured with a wide range of regulation, and the absence of an inner restraining wall on the impeller makes for high emciency and simplification of design. Furthermore our construction permits the use of low water heads in the reservoir ID, with shorter and stiffer motor extension parts,'better support of driver members, and a compact simplified assembly formed mainlyof loosely fitted sheet metal parts.

It is of course possible to make many modifications within the spirit of the invention as disclosed herein. Thus although the use of a rotary basket for supporting the tableware being washed is desirable, it is possible to use other types of supporting means, as will be apparent to one skilled in the art. Likewise while the pumping and spraying mechanism as illustrated gives good results, various modifications can be resorted to, including for example a shaping of the rotary impeller to depart from the use of a cylindrically 'wardly, in transverse cross-section said structure being annular in contour, animpeller disposed within the lower part of said structure, means serving to mount said impeller for rotation about a generally upright axis, said impeller being formed to impart rotary and vertical velocity components to liquid flowing thru said inflow opening, said impeller being also formed with a peripheral shroud, and a vertically movable member flvellillg said impeller, the peripheral edge of said enlber, together with the upper edge of said shroud, serving to define a variable annular orifice.

2. In a machine of the character described, a

hollow structure having its lower part formed to I afford an intake opening and having its upper part formed bowl-like, an impeller disposed withv in the lower part of said structure, means for mounting said impeller for'rotation about a generally upright axis, said impeller being formed to impart rotary and vertical velocity components to liquid flowing thru said intake opening and being likewise provided with a shroud about its outer periphery, a vertically movable'member overlying said impeller, the peripheral edge of said member, together with the upper peripheral edge of said shroud, serving to define an orifice of variable area, and means for throttling flow of. liquid through said intake opening.

use in conjunction with a liquid receiving reservoir, a bowl-shaped structure disposed within said reservoir, said structure ail'ording a. lower intake opening, means adjacent said intake opening for delivering liquid upwardly along the inner peripheral surface of said structure, and means forming-an adjustable orifice for admitting fiow I of liquid from said reservoir to said intake opening, there being a space between said adjustable orifice and said intake opening which is vented to the atmosphere.

5. In a machine of the character described for use in conjunction with a reservoir for receiving water, a bowl-shaped structure having a lower intake opening, a rotary impeller for delivering liquid upwardly along the inner peripheral surface of said structure, means for throttling flow of water through said opening from said reservoir, and means for maintaining a partially evacuated space within said impeller.

6. In a machine of the character described for use in conjunction with 'a liquid reservoir, a rotatable shaft extending upwardly through the bottom of said reservoir, a shroud surrounding said shaft and extending upwardly to a level above the level of liquid within said reservoir, said shroud being sealed with respect to the bottom wall of the reservoir, a bowl structure arranged to surround said shroud, the lower part of said bowl structure having an opening for iniiow of liquid, an impeller secured to the upper end of said shaft and arranged to surround said shroud within the lower part of said bowl structure, and means for throttling fiow of liquid from said reservoir through said intake opening.

7. In a machine of the character described, a generally upright hollow structure, in transverse cross-section said structure being annular in contour, lower part of said structure having an inflow opening and the upper part of said structure being belled outwardly, an impeller disposed within the lower part of said structure and rotatable about a substantially vertical axis, said impeller having an outer annular shroud, and a vertically movable closure member overlying the impeller, said closure member having an annular periphery co-operating with the upper edge of said shroud to form an annular discharge orifice.

8. In a machine of the character described, a stationary and generally upright bowl-shaped structure having a lower intake opening, an impeller disposed within said structure and adjacent said intake opening to impart rotary and upwardly directed velocity components to liquid, and means forming an automatically variable annular orifice for accommodating fiow of liquid from said impeller, said last means being within said structure and overlying the impeller.

9. In a machine of the character described, a generally upright hollow structure, in transverse cross section said structure being annular in contour, the lower part of said structure having an inflow opening and the upper part of said structure being belled outwardly, an impeller disposed within the lower part of said structure, means for rotating said impeller about a. substantially upright axis, said impeller being formed to impart both rotary and vertical velocity components to liquid flowing into said intake portion, and means overlying said impeller serving to define a variable annular orifice for delivery of liquid from the impeller to the inner peripheral surface of the upper part of said structure, said last means including a member movable in a direction sub stantially parallel to said axis.

10. In a washing machine, a stationary structure afiording a lower intake opening, said structure in transverse cross-section being annular in contour and having its upper portion belled upwardly and optwardly and substantially unobstructed with respect to discharge of liquid therefrom, the lower portion of said structure being of a diameter corresponding generally to the smallest diameter of the belled portion, and a rotary impeller disposed below said belled portion and within the lower portion of said structure for discharging a sheet of liquid upwardly along the inner peripheral surface of said upper belled portion, thereby causing the water to be discharged from the upper edge of said structure as a twisting conical spray.

11. In a machine of the character described, a bowl-shaped structure affording a lower intake opening, a rotary impeller for delivering liquid upwardly along the inner peripheral surface of said structure, and means making use of the aspirating effect of liquid flow from the impeller to said surface for maintaining a partially'evacuated space within the region occupied by said impeller.

GORDON B. GRACE. LOUIS P. IANSING. 

